Mine roof supports



April 1968 A. D. ALLEN 3,375,668

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ARcHELAius o. ALLEN I Q VAWQ A. D. ALLEN April 2, 1968 MINE ROOF SUPPORTS 6 Sheets-Sheet 6 Filed Feb. 21, 1966 N mi I-NVENTOR: D. ALLEN ARcHELAiu United States Patent 3,375,668 MINE ROOF SUPPORTS Archelaius D. Allen, Leyland, England, assignor to Gullick Limited, Wigan, Lancashire, England, a British company Filed Feb. 21, 1966, Ser. No. 528,986 Claims priority, application Great Britain, Mar. 4, 1965, 9,196/65 8 Claims. (CI. 61-45) This invention is for improvements in or relating to mine roof supports. The invention is particularly, although not exclusively concerned with self-advancing suports.

P In longwall methods of mining it is essential that the roof support units, which extend along the face, should give adequate support during the coal winning cycle.

Under some conditions, particularly where the roof has a tendency to break at the coal face so that the roof pressure has to be taken by the supports alone, there is a requirement for a support which can be positioned as close to the face as practicable without interference with the movement of the coal winning machine or the positioning or movement of other equipment at the face. An object of the present invention is to meet this requirement.

According to the present invention there is provided a mine roof support having a base which includes an elevated forwardly extending cantilever and at least one extensible roof supporting prop or leg mounted on said cantilever. I

By this arrangement, immediately after the coal winning machine has passed along the coal face the said leg or prop can be advanced towards the coal face, over the usual face conveyor, so that a roofing bar structure supported by said leg or prop can take up a forward position very close to the face and under the newly exposed roof.

In addition to providing space under the forward leg or prop so that it can be advanced over the conveyor, the arrangement according to the invention may also provide two distinct travelling tracks, one, at the rear of the cantilever being available, for example, for men walking along the face and the other on the upper part of the cantilever which can be used, for example, to carry rails or the like for a man-riding sledge or other vehicle.

In some preferred embodiments of the invention the support comprises forward and rearward elements each of which is provided with one or more hydraulically extensible legs or props. These forward and rearward elements may be mounted on a common base or each element may have its own separate base, the base of one element being articulated or pivotally linked to the base of the other.

Some embodiments of the invention will now be described, 'by way of example, with reference to the accompanying semi-diagrammatic drawings. In the drawmgs:

FIGURE 1 is a side elevation of one embodiment,

FIGURE 2 is a front elevation of the embodiment shown in FIGURE 1,

FIGURE 3 is a side elevation of a modification of the embodiment shown in FIGURES 1 and 2,

FIGURE 4 is a side elevation of a further modification of the embodiment shown in FIGURES l and 2,

FIGURE 5 is a side elevation of a further embodiment of the invention as applied to a longwall mining system using a conveyor mounted coal winning machine, e.g. a shearer loader,

FIGURE 6 is a front elevation of FIGURE 5, and

FIGURE 7 is a side elevation of a still further embodiment as applied to a longwall mining system using a face or floor mounted cutting machine (e.g. a trepanner) which is guided by a ramp plate or rail on the conveyor.

Referring first to the embodiment of the invention shown in FIGURE 1, the support comprises a rear element 10 and a forward element 11.

The rear element has a base 12 on which are mounted, in known manner, four hydraulically extensible props or legs 13 which, also in known manner, support at their upper parts a roofing bar structure 14.

The forward support element 11 comprises a frame having an elongated base member 15 formed integrally with a cantilever structure comprising a vertical part 16 and an elevated forwardly projecting cantilever part proper 17. I

It will be noted that the construction of the forward frame or base member 15, 16, 17 is such that it is open at its front part as indicated at 18.

Mounted on the cantilever 17, towards its forward end, is a single hydraulically extensible leg or prop 19 which supports a cantilever roofing bar structure 20 hingedly attached to the rear roofing bar structure 14 as indicated at 21.

The forward base member 15 is hingedly attached to the rear base member 12 by pivot means 22.

Where the props 13 are mounted on the base 12 and where the prop 19 is mounted on the cantilever 17 and also where the roof-bar structures 14 and 20 rest on the props the usual concave/ convex seating or other pivoting arrangements are provided to permit the props to tilt and the roof-bar and base structures to accommodate themselves to any irregularities in the floor or roof.

Pivotally mounted (e.g. by means of lateral trunnions which may be parts of the pivot means 22) in the base structure of the rear unit 10 is the cylinder 23 of a hydraulic ram having a piston rod or piston rod extension 24 attached or pivotally anchored at 25 to the spillplate 26 of the face conveyor C.

It will be noted that the base member 15 of the forward support element (which base member isrelatively narrow as can be seen from FIGURE 2) passes under and supports -the conveyor C. The latter is provided along its foremost edge with a ramp plate 27 which serves to direct the cut coal into the conveyor as the latter is advanced towards the coal face.

FIGURE 1 shows the position of a support unit before the passageof the coal winning machine. Afterthe machine has passed, the props 13, 19 are temporarily released and the hydraulic ram 23, 24 is retracted so that the support is brought forwardly to the position shown in FIGURE 3, the base member 15 of the forward support element sliding under the conveyor. It will be noted from FIGURE 3 that the roof-engaging structure 20 provides good roof support under the newly exposed roof right up to the coal face.

Following re-setting of the advanced support the hydraulic ram 23, 24 is extended so as to advance the conveyor again into the position shown in FIGURE 1. This pushing over of the conveyor causes the ramp 27 to plough the coal, not loaded directly into it by the cutting machine, into the conveyor.

It will be noted from FIGURE 1 that the construction above described not only provides the space 18 under the cantilever 17 to enable the forward part of the support to be advanced over the conveyor, so as to bring the roof-bar 20 up to the coal face, but also provides two distinct travelling tracks T1 and T2. The travelling track T1 may be used by men walking or crawling along the coal face whilst the track T2 may carry rails, which extend from support to support along the face, for a manriding sledge or carriage.

The embodiments of the invention shown in FIGURES 3 3 to 7 inclusive are similar in some respects to that already described with reference to FIGURES 1 and 2 and where applicable like reference numerals have been used to designate like parts.

In the embodiment shown in FIGURE 3 the base 12 of the rear element and the base 15 of the forward element are articulated together by means of resilient or spring tie-bars or links 28 pivotally connected to said bases at 28a and 28b.

In the embodiment shown in FIGURE 4 the base of the rear element and the base of the forward element 11 are combined into a common rigid base member 29 and the conveyor C is supported directly on the floor of the working.

In the embodiment shown in FIGURES 5 and 6 the construction is modified to suit cases where the coal cutting machine C1 is supported for movement entirely by the conveyor C. In this case the forward support element comprises two hydraulically extensible legs or props 19 and the rear element two legs or props 13. The roofbar structures are modified accordingly as indicated. The base 12 of the rear element is separate from the base 15 of the forward element. To connect the two together the base of the rear element is extended forwardly and is pivotally connected at 22 to the forward element. The anchorage 25 of the piston rod 24 to the conveyor includes a vertical slot arrangement which provides some freedom of movement in the anchorage.

FIGURE 7 shows the support adapted for use with a face mounted double-end coal winning machine C1. Here again, some modification and re-arrangement of the props and roof-bar structures has been made as indicated.

The cantilever 17 may be provided with a hydraulically downwardly extensible and upwardly retractable jack or prop as shown in dotted lines in FIGURE 1. This jack is retracted to allow the support to be advanced and is subsequently extended so as to bear on a convenient part of the support (e.g. the base 15) or floor and support the cantilever against bending stresses. In other words, the front of the support is not permanently open at 18 but is openable to allow the support to be advanced over the conveyor.

I claim:

1. In a mining system, in combination,

a mine roof support, said support including a base having a plurality of extensible props, a roof bar carried by said props above said base, a roof bar extension pivotally connected to said roof bar, a cantilever member connected to said base and projecting in a generally horizontal direction beneath 4 1 said roof bar extension in elevated position relative to said base to provide clearance space therebeneath, an extensible prop between said cantilever member and said roof bar extension,

a conveyor, and an extensible .ram connecting said conveyor to said base, said roof bar extension projecting beyond said cantilever member and said conveyor being disposed below the level of said cantilever member for disposition relative to said support between a position underlying said cantilever member within said clearance space and a position beyond said cantilever member and underlying the terminal end of said roof bar extension. 2. The system as defined in claim 1 wherein said cantilever member is pivotally connected to said base.

3. The system as defined in claim 2 wherein said base includes a forward extension projecting beneath and be" yond said cantilever member, said conveyor having a notched portion clearing and slidably supported on said forward extension of the base.

4. The system as defined in claim 1 wherein said ram is double acting.

5. A mine roof support as claimed in claim 1 wherein the cantilever comprises a substantially vertical upwardly extending limb and a forwardly projecting substantially horizontal limb on the upper part of said substantially vertical limb, the prop being mounted towards the free end of said substantially horizontal limb.

6. A mine roof support as claimed in claim 1 wherein the cantilever is of sufiicient length to provide a part which serves as an elevated travelling track.

7. A mine roof support as claimed in claim 1 wherein at least two props, located one behind the other, are mounted on the cantilever.

8. A mine roof support as claimed in claim 1 wherein the cantilever has a downwardly extensible and upwardly retractable jack positioned so that when extended it will support the cantilever against bending stresses.

JACOB SHAPIRO, Primary Examiner. 

1. IN A MINING SYSTEM, IN COMBINATION, A MINE ROOF SUPPORT, SAID SUPPORT INCLUDING A BASE HAVING A PLURALITY OF EXTENSIBLE PROPS, A ROOF BAR CARRIED BY SAID PROPS ABOVE SAID BASE, A ROOF BAR EXTENSION PIVOTALLY CONNECTED TO SAID ROOF BAR, A CANTILEVER MEMBER CONNECTED TO SAID BASE AND PROJECTING IN A GENERALLY HORIZONTAL DIRECTION BENEATH SAID ROOF BAR EXTENSION IN ELEVATED POSITION RELATIVE TO SAID BASE TO PROVIDE CLEARANCE SPACE THEREBENEATH, AN EXTENSIBLE PROP BETWEEN SAID CANTILEVER MEMBER AND SAID ROOF BAR EXTENSION, A CONVEYOR, AND AN EXTENSIBLE RAM CONNECTING SAID CONVEYOR TO SAID BASE, SAID ROOF BAR EXTENSION PROJECTING BEYOND SAID CANTILEVER MEMBER AND SAID CONVEYOR BEING DISPOSED BELOW THE LEVEL OF SAID CANTILEVER MEMBER FOR DISPOSITION RELATIVE TO SAID SUPPORT BETWEEN A POSITION UNDERLYING SAID CANTILEVER MEMBER WITHIN SAID CLEARANCE SPACE AND A POSITION BEYOND SAID CANTILEVER MEMBER AND UNDERLYING THE TERMINAL END OF SAID ROOF BAR EXTENSION. 